What driver version did you get?

Hi, I agree with M Diamond. 5GHz is only useful to increase the throughput or when there is a lot 2.4GHz signals around you...

Hi, T2UH uses a MediaTek MT7610U chip, try to find the latest driver on the web...

Sorry, I made a mistake. WN821N v4 uses a Realtek RTL8192CU chip not Qualcomm... http://www.station-drivers.com/index.php/downloads/Drivers/Realtek/WLan/RTL8192RU-8188CU-8188CUS-8192CU..../

Hi, Try the best driver from here: http://www.station-drivers.com/index.php/downloads/Drivers/Qualcomm-Atheros/WLan/AR5xxx-9xxxx-Serie/

Hi, Try a driver from here: http://www.station-drivers.com/index.php/component/remository/Drivers/Qualcomm-Atheros/WLan/AR5xxx-9xxxx-Serie/orderby,2/page,2/?Itemid=0